On Oct 11, 2011, at 5:31 AM, Roger Burton West <[email protected]> wrote:
> On Tue, Oct 11, 2011 at 05:29:32AM -0500, Captain Joy wrote: >> I'm not sure I understand; in fact I'm sure I don't. If you know where on >> the ellipse your planet is at at t=0, and you know the semi-major axis and >> eccentricity of the orbit, it seems like figuring what angle the planet >> moves through each Delta t thereafter should be a fairly simple equation. > > It isn't. > > You can take Hal's approach and slice the orbit into smaller and smaller > delta-T segments, working out the swept area. Or you can use calculus. > But neither of these is going to be _simple_. No, but the angle a planet moves through given its current location on the ellipse, semi major axis, delta-T, and eccentricity is an equation that can be looked up. -- Captain Joy [email protected] _______________________________________________ GurpsNet-L mailing list <[email protected]> http://mail.sjgames.com/mailman/listinfo/gurpsnet-l
